[lvc-project] [PATCH] i2c: Fix NULL pointer dereference in npcm_i2c_reg_slave

[Fedor Pchelkin]

Hi Rand,

On 24/01/09 05:51PM, Rand Deeb wrote:
> In the npcm_i2c_reg_slave function, a potential NULL pointer dereference
> issue occurs when 'client' is NULL. This patch adds a proper NULL check for
> 'client' at the beginning of the function to prevent undefined behavior.

Could you please explain how npcm_i2c_reg_slave() can be called with a
potential NULL argument?

It is called via a function pointer ->reg_slave. As for 6.7 release, I 
can only see it called from i2c_slave_register() here [1], and it seems
client definitely can't be NULL there.

Maybe it can happen for another kernel release (not upstream)?

[1]: https://elixir.bootlin.com/linux/latest/source/drivers/i2c/i2c-core-slave.c#L48